Comb Ridge

Grooves in a sandstone cliff reveal ancient tool sharpening

Feb. 21, 2024

By rubbing a spear head against stone to form or sharpen it, a groove is gouged very similar to the grooves beside the Procession Panel.

Researcher on top of concrete block submerged in the ocean.

A Lesson from the Past?

Dec. 20, 2022

Marine concrete from the Roman empire has proven to stand the test of time—and offers insights into ways to combat rising sea levels now.